GB2414392A

GB2414392A - Additional wheels for patient transport means

Info

Publication number: GB2414392A
Application number: GB0517330A
Authority: GB
Inventors: Philip Ward
Original assignee: Ferno UK Ltd
Current assignee: Ferno UK Ltd
Priority date: 2001-06-29
Filing date: 2001-06-29
Publication date: 2005-11-30
Anticipated expiration: 2021-06-29
Also published as: GB2414392B; GB0517330D0

Abstract

Patient transport means 10 has at least one set of wheels 60, the or each set of wheels 60 comprising at least two wheels 62 which may rotate about their own respective axes as well as about a common axis of the set of wheels 60, and which is connected to the transport means 10, the transport means 10 having at least one further set of wheels 200, the or each further set of wheels 200 comprising at least two wheels 202 which may rotate about their own respective axes as well as about a common axis of further set of wheels 200, the or each further set of wheels 200 being selectively attachable to, and detachable from, the transport means 10. The further set of wheels 200 may be attached to an existing set of wheels 60 preferably with their respective axes aligned.

Description

PATIENT TRANSPORT APPARATUS

The present invention relates to mobile chairs and to a method of moving chairs and mobile chairs. The present invention also relates to patient transportation means and a method of adapting patient transportation means. The invention is particularly, although not exclusively, applicable to chairs that are for use in an emergency such as chairs for evacuating buildings or retrieving patients from remote areas and chairs for manoeuvring patients.

In patient transporting chairs it frequently occurs that the patient is stranded on a beach or other soft surface.

The wheels on chairs that might be desirable to use in this location sink into the ground and prevent the chair being able to be used. Accordingly a patient has to be loaded onto a stretcher, carried off the beach, up steps and then transferred to a chair. This prolongs the rescue of a patient and risks damage to the backs of the stretcher bearers.

Patient transporting chairs are often stored in places where space is tight, such as in an ambulance. However, even when the chairs can be folded up they can still take up a substantial amount of valuable space.

It is an object of the present invention to attempt to overcome at least one of these or other problems.

According to one aspect of the present invention, a mobile chair includes at least one upwardly extending portion that connects a backrest, seat and wheels, in an operative position in which a person can sit on and be manoeuvred by an operative, the chair being movable to a storage position in which the previously upwardly extending portion is in two parts, one of which includes the wheels and the other of which includes at least the backrest and may also include the seat.

According to a further aspect of the present invention a mobile chair includes at least one upwardly extending portion that connects a backrest, seat and wheels in an operative position in which a person can sit on and be manocuvred by an operative, the chair being movable to a storage position in which at least parts of the upwardly extending portion are at least partly coextensive with each other.

When moving to the storage position, the parts may remain connected to each other such as by being pivoted relative to each other.

In the storage position, the previously upwardly extending portion may be in two separate parts. Those parts may include cooperating portions which, in the operative position restrict relative lateral movement transverse to the general elongate extent of the upwardly extending portion and, alternatively or additionally, may also restrict relative pivotal movement about the general elongate extent. The cooperating portions may include a male member associated with one part and a female member associated with the other part. The means for restricting relative pivotal movement may comprise connection means that attach the seat to one part also restricting relative pivotal movement.

In the storage position, one part may be connected to the other part, for instance by attachment means which may comprise clip means such as spring clip means.

The upwardly extending portion may comprise a single upwardly extending portion which may be centrally located between each side of the chair.

According to another aspect of the present invention, a method of moving a mobile chair from an operative position, in which a person can sit on a chair and be manoeuvred, to a storage position comprises moving a support for the chair that is connected to a seat, backrest and wheels in the operative position to a configuration in which the support is in two parts, at least one of which contains the backrest and the other of which contains the wheels.

The method may comprise moving the support in two separate parts or moving the parts whilst the parts remain connected such as by pivotal movement of the parts.

The method may comprise connecting the two parts together in the storage position.

According to another aspect of the present invention a method of moving a mobile chair from an operative position, in which an upwardly extending portion supports wheels, a backrest and a seat, to a storage position comprises locating parts of the upwardly extending portion to be at least partially side-by-side.

The method may comprise securing or, alternatively or additionally connecting those parts together in the storage position. The method may comprise moving the parts to the storage position whilst the parts are connected such as by pivoting the parts relative to each other.

The present invention includes moving a mobile chair from an operative position to an inoperative position when the chair is as herein referred to.

According to another aspect of the present invention patient transportation means include a support means for a patient and wheels attached to the transportation means which enable the transportation means to travel, characterized in that at least one further wheel is provided which may be selectively attached and detached from the transportation means whereby the transportation means is able to be more manoeuvrable on a softer surface.

The further wheel may be arranged to be provided in addition to the wheels previously present on the transportation means. The further wheel may be arranged to be attached to an existing wheel and to be attached such that its rotational axis is aligned with the rotational axis of an existing wheel or both.

The further wheel may have the same profile or same inflation pressure or same resistance to pressure or same friction properties or any combination thereof as a wheel that was present on the transportation means before the attachment of the further wheel.

The further wheel may be detachably connected by axial and turning motion, for instance with that movement locating a part on one of the further wheel or the wheel on the chair behind another part to prevent axial movement to detach the further wheel. The axial movement may be arranged to be against a resilient bias. The resilient bias may remain when the further wheel is connected.

The wheels that are attached to the transportation or the further wheel that is to be attached or both may include at least one set of wheels with the or each set comprising at least two wheels and preferably three wheels each rotatable about their own axis with each of those wheels being rotatable about a common axis, which may be parallel to each wheel axis, spaced from each wheel axis. The common axis may be equidistant from each wheel axis.

According to a further aspect of the present invention, a method of adapting patient transportation means whereby the transportation means is able to be more manoeuvrable on a softer surface comprises connecting at least one wheel to the transportation means.

The method may comprise adding at least one additional wheel to existing wheels.

The present invention also includes adapting a patient transportation means as herein referred to when the patient transportation means is as herein referred to.

The present invention also includes patient transportation means when adapted by a method as herein referred to.

The patient transportation means as herein referred to may comprise a chair.

According to one aspect of the present invention a chair includes at least one wheel assembly constrained to rotate about an assembly axis, the or each wheel assembly comprising a plurality of wheels with each wheel being rotatable about its own wheel axis.

The chair may include means arranged to resist rotation of the wheel assembly about the assembly axis.

The means to resist rotation about the assembly axis may comprise means to prevent rotation about the assembly axis.

Those means to prevent rotation about the assembly axis may comprise locking means.

The locking means may comprise a retractable plunger movable from a first position in which the plunger engages the wheel assembly and another part of the chair and a second position in which the plunger is disengaged from the wheel assembly.

The plunger may be movable by a pivotal cam.

The plunger may be biased towards the first position.

The locking means may be arranged to cooperate with an axle portion defining the assembly axis. The locking means may be arranged to cooperate with the axle portion in a central region of the axle. The locking means may be arranged to cooperate with the axle such that the axle can be locked in one of a plurality of positions. For instance three.

These positions may be equally angularly spaced from each other.

The means to resist rotation about the assembly axis may comprise a brake. The brake may be arranged to induce friction to resist rotation. The brake may be arranged to vary the friction force.

The brake may comprise an arcuate member.

The arcuate member may be pivotally connected to the chair and movable about that pivot to apply or increase friction or to remove or decrease friction or any combination thereof. The pivot of the arcuate member may be arranged to be caused by an operating means. The operating means may comprise a threaded portion that is arranged to engage with a threaded member whereby relative rotation of the threaded portion and the threaded member is arranged to cause axial movement of the threaded portion to cause pivotal movement of the arcuate member.

Relative rotation of the threaded portion to the threaded member may be arranged to occur in opposed directions to cause axial movement of the threaded portion in one of two opposed directions.

The operating means may include moveable means for engaging and disengaging the threaded portion whereby reciprocal movement of the movable means is arranged to cause rotational movement of the threaded portion in one rotational direction only by engaging the threaded portion when moving the operating member in one direction of the reciprocal movement and disengaging this threaded portion in the opposite direction of reciprocal movement.

The assembly axis may be defined by an axle. The brake may be arranged to act on a downwardly facing portion of the axle. The brake may be arranged to engage with an enlarged portion of the axle.

The brake may comprise a pivotal operating member movable between a first position in which a brake portion does not have any significant braking effect and a second position in which the brake member is urged to resist rotation of the axle. Movement of the operating member may be arranged to move the brake between both positions.

The operating member may be arranged to be in an over centre position when in at least one of the positions. For instance, when the brake is applied, the operating member may have to go through a pivotal position in which more force would be applied to the brake prior to returning to the first position. Alternatively or additionally resilient means may be arranged to bias the brake into an operative or inoperative position or both.

The operating member may be connected to a rotatable shaft at a location radially offset from the longitudinal axis of the shaft.

The brake may be adjustable whereby the length of the brake portion from the operating member to the axle is adjustable, for instance by rotating a threaded portion of the brake portion.

The brake may be operable by the foot of an operator, for instance both to apply the brake and to remove the brake.

The chair may include an axle defining the wheel assembly axis. The brake and the locking means may be arranged to cooperate with the same axial extent of the axle. The brake and locking means may be arranged to act on opposite sides of the axle. The brake and the locking means may be arranged to cooperate with an enlarged portion of the axle.

The brake or alternatively or additionally the locking means may have the parts that cooperate with the axle concealed.

The or each wheel assembly may comprise three wheels.

The chair may include two wheel assemblies at opposed side regions of the chair. The two wheel assemblies may be constrained to rotate together about a common axis.

According to a further aspect of the present invention a method of moving a chair including at least one wheel assembly that is constrained to rotate about an assembly axis in which the or each wheel assembly comprises a plurality of wheels with each wheel being rotatable about its own wheel axis comprises providing a support for the chair by at least one wheel from the or each wheel assembly and rolling the chair on at least one wheel.

The method may comprise providing support for the chair by at least two wheels of the or each wheel assembly.

The method may comprise preventing rotation of the assembly axis relative to the remainder of the chair whereby a single wheel of the or each wheel assembly is able to provide the support for the chair.

The method may comprise imposing a braking force on the assembly axis whereby resistance to rotation about the assembly axis is imposed. The method may comprise varying that resistance. The method may comprise imposing the resistance to rotation about the assembly axis when the chair is being moved down steps or down stairs.

The method may comprise the wheel assembly rotating about the assembly axis when the chair is being moved up or down steps or stairs such that successive wheels of the or each wheel assembly are caused to engage with the step or stairs. The method may comprise the chair pivoting about both a wheel axis and the assembly axis as the chair undergoes at least a part of its movement relative to steps or stairs. The method may comprise at least two wheels engaging the step or stairs as the chair undergoes movement relative to the step or stairs. The method may comprise at least two wheels of the or each wheel assembly rotating about their wheel axis as the chair undergoes movement along the step or stairs. The method may comprise one wheel rotating about its wheel axis and engaging an upwardly facing portion of a stair and another wheel engaging a generally horizontal portion of a step and rotating about its wheel axis or stair simultaneously as the chair is moved relative to the step or stairs.

According to another aspect of the present invention a foldable chair includes a backrest, a seat and a foot rest, the seat and foot rest being movable relative to the backrest from an operative position in which the backrest projects upwardly, the seat projects forwardly and the foot rest is located at a lower elevation than the seat to a storage position in which the seat is located adjacent to the backrest and the foot rest is located adjacent to the seat.

In the storage position, the backrest, seat and foot rest may be generally parallel to each other. In the storage position at least two of the backrest, the seat and the foot rest may be in contact with each other and preferably all three of the backrest, seat and foot rest are in contact with each other.

In the operative position the foot rest may be arranged to extend downwardly and forwardly. In the operative position the backrest may be arranged to extend upwardly and rearwardly.

At least one of the seat and foot rest, and preferably both, are pivotally mounted on the chair and the seat and/or the foot rest may be pivotally movable between the operative and the inoperative position.

According to another aspect of the present invention a foldable chair includes a backrest, a seat and a foot rest, the foot rest being movable between an operative position in which the foot rest is located at a lower elevation than the seat and a storage position, the chair including releasable means arranged to retain the foot rest in the operative position.

The releasable means may comprise a retractable plunger arranged to engage with a part of the foot rest to resist movement of the foot rest away from an abutment.

According to another aspect of the present invention a foldable chair includes a backrest, a seat and a foot rest, the seat being pivotally mounted on the chair between an operative position in which the seat extends forwardly and a storage position in which the seat is pivoted upwardly, the seat, in the operative position, abutting with a portion of the foot rest to resist further downwards movement of the seat about its pivotal mounting.

The foot rest may be arranged to be pivotally mounted on the chair. The seat may be arranged to abut with the foot rest in the region of the pivotal mounting of the foot rest when the seat is in the operative position.

According to a further aspect of the present invention a chair includes a backrest, seat, foot rest and an upper handle portion, the handle portion being arranged, in use, to be located at a higher elevation than the backrest.

The height of elevation of the handle portion may be adjustable, for instance between a plurality of positions and the height of elevation of the handle portion may be arranged to be releasably held in a plurality of positions.

The configuration of the handle portion with respect to the remainder of the chair may be arranged to be adjustable and may be arranged to be held releasably in a plurality of different positions. One position of adjustment of the handle portion may be such that the handle portion extends to elevations substantially co-extensive with the elevation of other parts of the chair and another position in which the handle portion is at an higher elevation than other parts of the chair.

The handle portion may comprise a pair of handles and those handles may be arranged to extend towards each ocher and those handles may be arranged to have an extent in a substantially horizontal direction.

The handle portion may comprise a single member. The single member may be arranged to be pivotally movable on the chair.

The present invention also includes a method of operating a chair including a handle portion with the chair being substantially as herein described. The method may comprise using the handle portion to manoeuvre the chair up a step or stairs, or down a step or stairs, or along the horizontal, or any combination thereof.

According to a further aspect of the present invention a chair includes a backrest, a seat and a foot rest and a lower handle portion.

The lower handle portion may be arranged to project forwardly from the foot rest and may project forwardly and downwardly from the foot rest or downwardly from the foot rest or any combination thereof.

The handle portion may comprise a pair of handles spaced from each other.

The lower handle portion may include a pair of handles arranged to project forwardly from each side of the foot rest.

The handle portion may be arranged to occupy a plurality of positions and may be arranged to be releasably held in those positions.

The lower handle portion may comprise a pair of handles and the handles may be arranged to occupy a position in which they are substantially co-extensive, for instance side-by- side with, the foot rest.

The handle portion may be arranged to extend forwardly and upwardly from the foot rest.

The handle portion may comprise a single member and that single member may be arranged to be pivotable between a IS plurality of different positions.

The lower handle portion may be connected to the foot rest and may be constrained to move within the foot rest.

The present invention also includes a method of using a chair having a backrest, a seat, a foot rest and a lower handle portion as herein referred to. The method may comprise pushing against the lower handle portion to resist movement of the chair down a step or stairs or to urge the chair up a step or stairs or any combination thereof.

The present invention also includes a chair including a backrest, a seat and a foot rest in which the chair includes a support extending upwardly in the middle region of the chair.

Any or all of the foot rest, backrest, seat or wheel assemblies may be connected to the support in the central region. The upper handle portion may be adjustable relative to the support. The seat or the foot rest or both may be pivotally connected to the support. The brake or the locking means or both may be at least partially concealed within the support.

The or each wheel assembly may be rotatably connected to the bottom region of the support.

According to a further aspect of the present invention, a chair incorporates a seat, a backrest and a handle portion, the seat and backrest being movable relative to each other between an operative position and a storage position in which, in the storage position, the handle portion is arranged to retain the seat and backrest together.

The handle portion may be movable, in the storage position, between a first position in which the seat and backrest can move relative to each other and a second position where that relative movement is inhibited. The movement of the handle portion may be pivotal. Locking means may be provided to retain the handle in the second position.

In the operative position the handle portion may be an upper handle portion.

The handle portion may comprise a pair of handles.

The seat may include a foot rest that is also movable between the operative position and the storage position.

The foot rest may also be arranged to be retained in the storage position by the handle portion.

The present invention includes any combination of the herein referred to features or limitations.

The present invention can be carried into practice in various ways but several embodiments will now be described by way of example, and with reference to the accompanying drawings in which: Figure 1 is a side view of a chair 10 in an operative position; Figure 2 is a side view of the chair 10 in a storage position; Figure 3 is a detailed view of the rear of the base of the chair showing the mechanism that retains a foot rest of the chair in an operative position; Figure 4 is a view similar to Figure 3 that shows a locking mechanism for a wheel assembly of the chair; Figure 5 is an underneath view of part of the chair showing a brake mechanism; Figure 6 is a perspective view of a second embodiment of a chair 110 in an operative position; Figure 7 is a schematic side view of a brake and locking mechanism employed for the chair 110; Figure 8 is a detail view of a locking mechanism for a foot rest for the chair 110; Figure 9 is a view from underneath of part of the brake mechanism for the chair 110; Figure 10 is a schematic side view of an additional set of wheels 200 that can be added to any of the wheels described in the previous embodiments; Figures 11 and 12 are side and end views respectively of the attachment included on the wheels 200 that enable the connection or removal of the set of wheels 200; Figures 13 and 14 are end and side-sectional views of the attachment used with the existing wheel sets to allow the set 200 to be attached and detached, and Figures 15, 16 and 17 are, respectively, a front sectional view of a top half of the spine of a chair that can be detached, a front sectional view of the bottom half of such a spine and a side view of part of Figure 16.

As shown in Figure 1, the chair includes a seat 30 on which, in use, a person to be transported sits with their feet resting on a downwardly and forwardly inclined foot plate 32 with their back being supported by an upwardly and rearwardly inclined backrest 34.

As shown in Figure 6, the foot rest 132 is defined by a series of three parallel bars which can rest on the ground and on which a patients feet can rest. In this embodiment a patients lower legs can extend straight down from their upper legs with the feet resting in a flat position.

Straps (not shown) may surround a patient's legs to hold them together on the foot plate 32 or foot rest 132. These straps may be fastened by cooperating hooks and eyes, for instance, to make the straps easily attachable and detachable. The strips may be connected to either side of the foot plate or they may be connected to the rear of the foot plate or they may extend over the complete under surface of the foot plate.

A harness (not shown) may be connected to the backrest 34 or 134 or to the rear of the backrest 34 or 134. Straps of the harness may go over each shoulder and under each arm to be detachably connected across the chest of a person.

The straps of the foot rest and the harness hold the person securely on the chairs. This is of particular importance where the chairs have to be moved in a hurry or where the chairs have to negotiate steps where the operatives controlling the chair will need their hands free to manoeuvre the chair.

The seat 30 or 130 are supported by and connected to a pair of bars 36 that are pivotally connected to a central tubular trunk 33 or 138 of the chair. The bars 36 extend in a straight direction beneath the seat 30 or 130 before extending upwardly from the rear of the seat, to the axially aligned pivots 40 at each side of the trunk, as shown in Figure 1. The foot rest 32 is supported by and connected to generally straight parallel bars 42 or 142 that extend upwardly and rearwardly from the foot rest before extending generally upwardly to pivots 44 on each side of the trunk 33.

In the position shown in Figures 1 and 6, downwards movement of the seat 30 or 130 about the pivots 40 is prevented by abutment of the bars 36 of the seat with the mounting for the pivots 44 of the bars 42 or 142.

In the operative position shown in Figure 1, downwards movement of the foot rest is prevented by abutment of a cross bar 46 extending between the bars 42 with a screw stop 48 extending forwardly from the trunk, as shown in Figure 3. The extent of the screw stop 48 from the trunk can be adjusted by rotating the screw 48 to cause the stop 48 to move in a translational direction towards or away from the trunk. A plate 50 extends forwardly from the trunk just below the stop 48. A plunger 52 projects upwardly through the plate. When the cross bar 46 abuts the stop 48, forwards movement of the cross bar is prevented by abutment with the plunger 52. In this way the footplate is locked in position relative to the trunk. The plunger can be retracted down through the plate 50, against a spring bias, by pulling downwardly on a knob 54 located beneath the plate and connected to the plunger. In the retracted position of the plunger the footplate can be moved about its pivot to allow the cross bar to move towards or away from the stop 48.

In Figure 8 a plunger 152 is mounted on a cross bar 153 of the foot rest. A bracket (not shown) is secured to the trunk 138 and, in the operative position, is located beneath the plunger 152. The plunger can be pulled to be retracted against a spring force. When released the plunger extends through the cross bar 153 into an opening in the bracket to prevent movement of the foot rest relative to the trunk. The foot rest can be freed to allow it to be collapsed by retracting the plunger from the opening in the bracket.

The chairs can be moved from the operative position shown ln Figures 1 and 6 to the storage position shown in Figure 2 by moving the seat 30 or 130 upwardly about the pivots 40 until the seat 30 or 130 extends upwardly and rearwardly, flat against the backrest 34 or 134. Then the plunger 52 or 152 is retracted to release or free the cross bar and allow the foot rest 32 or 132 to be moved upwardly about the pivots 44 until the foot rest lies flat against what is normally the underside of the seat. In this position the planes of the backrest, seat and foot rest are generally parallel to each other and they are closely adjacent to each other or in contact with each other to provide a compact storage configuration. If desired, straps can be provided to secure the backrest, seat and foot rest together in the storage configuration. Alternacively, the handles 184 shown in Figure 6 can be pivoted through 180 to bring the handles over the foot rest and seat to retain them in the storage position. In thatconfiguration, one of the bars of the foot rest 132 projects above the handle to manocuvre the chair on the wheels to lift the chair to a storage position.

The trunk 38 or 138 includes a lower tubular hollow branch 56 or 156, shown in Figures 3 and 6, through which an axle 58 (shown in Figure 4) is rotatably mounted. The axle rotatably supports wheel assemblies 60 or 160 at each side of the chair.

Each wheel assembly 60 or 160 includes three wheels 62 or 162 that are axially aligned with each other. The pivot axis of each wheel 62 or 162 is spaced an equal radial distance from, and an angular extent around the longitudinal axis of the axle 58. The mounting of each wheel 62 or 162 is provided by a pair of brackets 64 or 164 that are fixed to the axle 58 and that provide a pivot for each wheel 62 or 162 extending across the brackets 64 or 164 through each wheel.

In the storage position of the chair shown in Figure 2, two of the wheels 62 or 162 at each side provide support for the chair. The trunk 38 or 138 though is able to pivot about the axle 58. That would make the chair unstable if the only support for the chair were provided by the wheels 62 or 162 and the chair would fall from the position shown.

Accordingly axle and trunk locking means shown in Figure 4 are provided to prevent relative rotation of those parts.

The locking mechanism for the chair 110 shown in Figure 6 will be described later.

The locking means comprises a plate 66 extending upwardly from one side of the branch adjacent to the inside bracket 64 of a wheel assembly 60. A retractable plunger 67 extends through the plate into a hole (not shown) in the bracket 64. With the plunger being located in the hole in the bracket, the bracket is not able to rotate relative to the branch or trunk and the axle 58 is fast with the trunk.

The plunger can be retracted against a spring force, by pivoting a lever 68 from the horizontal position shown in Figure 4 to an upright position. During that movement of the lever 68 a cam is engaged to cause axial movement of the lever and the plunger to which it is connected to retract the plunger from the hole. Insertion of the plunger into the hole is achieved by moving the trunk about the axle 58, if necessary, to align the plunger with the hole in the bracket and pivoting the lever 68 back into the horizontal position to allow the spring to push the plunger into the locking position.

The chair 10 is also provided with a brake to inhibit free rotation of the trunk 38 about the axle 58. The brake for the chair 110 will be described later.

The brake is located at the base of the trunk, as shown in Figure 5. The brake comprises an operative member 70 connected by a pivot 72 at one side of the trunk and extending around the base of the trunk where it is connected to rod 74 that extends up the other side of the trunk through a bracket 76 extending from the rear of the trunk. The rod 74 can be moved up and down along the trunk by means described below to cause the member 70 to move about the pivot 72.

The upwardly facing surface of the member 70 includes an arcuate friction member (not shown) that is arranged to cooperate with a friction disc 78 secured to the axle 58 and projecting through the lower end of the trunk.

As the rod 74 is moved upwardly the operative member 70 is moved about the pivot 72 to cause the friction member to engage with the friction disc to inhibit relative rotation of the axle 58 and the trunk 38. Further upwards movement of the rod causes that resistance to relative movement to be increased. Ultimately the brake can lock the axle 58 and trunk together.

Movement of the rod 74 is achieved by a control lever 80 above the bracket 76 and through which the rod extends.

The rod 74 threadably engages the bracket 76 such that relative rotation of the rod causes up or down movement of the rod along the trunk.

The lever 80 is pivotally connected to the bracket such that a socket (not shown) in the base of the lever can selectively engage with a nut on the top of the rod.

Adjustment of the rod is achieved by pivoting the rod in an upwards direction to engage the socket with the nut and then rotating the lever in one direction to cause the rod to rotate. Then the lever is pivoted in a downwards direction to disengage the socket from the nut and the lever is rotated in the opposed direction without rotating the rod. By repeating this sequence the rod can be repeatedly rotated in one direction to raise or lower the rod and to increase or decrease or remove the brake, depending on the direction of rotation when the nut and socket are engaged.

The locking mechanism of the chair 110 will now be described.

A plate 166 is secured to the trunk 138 adjacent to the bottom of the trunk. A retractable plunger 167 extends through the plate 166 and the trunk 138 towards a friction disc 178 that is fast with the axle 158. The plunger is able to be biased towards the disc to rest in one of a series of three holes 169 that are equally spaced in the circumferential surface of the disc 178. When located in one of the holes the axle 158 is fast with the trunk and the wheel assemblies are always in the same configuration with respect to the trunk, even though each wheel may be in one of three possible positions.

The plunger can be retracted against a spring force by pivoting a lever 168 to cause a cam to be engaged to cause axial movement of the plunger.

The plunger is applied by a spring force against the disc by moving the lever in the opposite direction. The chair can then be moved to rotate the axle until the plunger is aligned with, and moves into one of the holes 139.

The brake for the chair is also located in the bottom of the trunk. It includes a brake liner 171 on a block 173 that can act against the upwardly facing surface of the disc 178.

The top of the block 173 is attached to a threaded rod 175 that is locked in position by a nut 177. The nut 177 can be slackened and the rod can be screwed into or out of the block, before tightening the nut 177 again, to alter the extent of the rod 175 from the block to adjust the effective length of the assembly and the breaking force, for instance to take account of wear of the friction surfaces.

The top of the rod includes a cylindrical opening. A bolt 179 is passed through that opening and threadably engages with the end of a shaft 181 off centre from the longitudinal axis of the shaft 181.

The shaft 181 extends through the trunk 138 and is rotatably mounted in a bush 183 on the side of the trunk.

A bolt 185 threadably engages with the bush 183 and extends into a circumferential groove of the shaft 181 to axially locate the shaft.

A foot pedal 187 is secured to the free end of the shaft.

Bushing the pedal down causes the bolt 179 to move from a position in which its centre is generally at the same height as the axis of the shaft, round to a position in which the centre of the bolt is generally beneath the axis of the shaft. This movement causes the top of the rod 175 to move in an arcuate direction downwardly and to the right to apply the brake. If desired, this position may be such that the axis of the rod 175 extends over centre, to the right of the axis of the shaft 181 such that the rod resists movement in the reverse direction as such movement would tend first to urge the brake more firmly into engagement before the brake was released.

The brake is removed by a user pushing up with their foot on the underside of the pedal 187 to cause the bolt 179 to move back, taking with it the rod 175.

If desired, the pedal can be raised until the axis of the rod 175 again passes to the right of the axis of the shaft 181 in an over centre position to prevent the brake from coming on again.

Alternatively or additionally, a spring may be connected, such as a compression spring between the pedal or an extension of the pedal such that, with the pedal pushed down to apply the brake, the spring urges the brake on, and, with the pedal in the raised position, the spring acts to hold the pedal up and the brake off.

The bottom of the trunk may include a cap 189 to protect the brake and locking mechanism from the environment.

The chair 10 or 110 has many modes of operation including: movement up stairs or steps; movement down stairs or steps, and movement along a nonstepped surface.

Referring first to movement upstairs or steps, the axle is able to rotate relative to the trunk. The chair is reversed towards the steps by a first operator tilting the trunk rearwardly by pushing down and rearwardly on upper handles 84 at the top of the chair to raise the foot rest and associated lower handles 82 or 182 clear of the ground.

Then that operator pulls the handles 84 or 184 rearwardly to cause the chair to roll rearwardly over the ground on two pairs of wheels 62 or 162 at each side of the chair.

When one wheel 62 or 162 at each side of the chair abuts the vertical surface of a step a second operator grips the lower handles. Then the first operator pulls on the upper handles 84 or 184, generally in the line of inclination of the steps, and the lower operator may, optionally, apply a lifting force or a pushing force or both.

The first wheels 62 or 162 that engage with the base of the step remain in position and the wheel assemblies 60 or 160 pivot about the axis of the axle 58 to cause the wheels 62 or 162 of the assemblies that previously provided no ^7 support for the chair to move towards engagement with the step and to raise the remaining wheels clear of the ground.

The wheel assemblies continue to rotate to bring successive wheels into contact with the steps as the chair is being moved up the stairs. Thus the wheels provide vertical support for the chair over the majority of the movement of the chair. Furthermore, as the wheels engage with the vertical part of the steps control is provided on the movement of the chair up the steps.

For steps having large horizontal surface two wheels will briefly be in contact with the step as the chair is advanced along that step until the leading wheels abut the base of the next vertical step. As the chair is being lifted following that abutment succeeding wheels may abut the vertical extent of the steps as the chair is being raised, together with the wheel that abutted the base of the step to roll the chair up. Alternatively, the wheel succeeding that at the base may engage the flat surface of the next step or the corner between the horizontal and vertical parts of the step to cause both wheels to ride around the corner.

To descend stairs the brake can be applied to an extent, if desired, to stop the chair tending to run away down the stairs and to ease the load on the operators to resist that movement. The chair is pushed along the ground towards the stairs in a forwards direction by an operator gripping the handles 84 or 184 and with the chair being tilted back slightly such that two pairs of wheels at each side support the chair.

As the top of the stairs are approached, an operator already part of the way down the stairs grips the lower handles 82 or 182. The operators then provide resistance, if required, to the force of gravity moving the chair down the stairs with the wheel assemblies and the axle 58 moving and engaging with the steps substantially as previously described. The lower handles, in the position shown, extend downwardly and forwardly from the foot rest, generally in the direction of the foot rest. Consequently the lower operator is clear of the foot rest and the feet of a person on the chair. Furthermore, the lower operator can take the handles and control movement of the chair without necessarily having to bend at all, and may only have to push against the handles.

To move the chair along flat ground, only one operator need be used who grips the upper handles 84 or 184. To make the chair more manoeuvrable, the wheel assemblies and the axle can, optionally, be locked in position relative to the trunk either by the brake, or more probably, by locking the brackets of the wheel assemblies. Then the chair can be tipped back such that support is provided by one wheel only at each side. This allows the chair to be manoeuvred, forwards or backwards, and around corners without there being resistance such as would be provided if two supporting wheels at each side had to scrape round the corner.

The lower handles are able to occupy more than one position relative to the foot rest. In the figures the handles are shown as projecting forwardly from the foot rest in the general plane of the foot rest. These handles though could be pivoted to a position in which they extend alongside the foot rest in the plane of the foot rest. This provides a compact configuration when the chair is being manoeuvred on a flat surface or is useful when the chair is being stored.

The lower handles are able to occupy a third position in which they extend upwardly, generally at right angles to the plane of the foot rest. This position is particularly useful when the chair is being lowered down stairs as it enables the lower operator to push or lean against the handles to provide resistance to the chair moving downstairs.

The upper handles are also able to occupy more than one position. Although the upper handles are shown in Figures 1 to 5 as being a straight cross-bar in practice each end of the bar may include parallel bars that extend first away from the axial extent of the cross-bar and then back, to a small extent, towards each other to allow that small extent, known as a hand grip, to be held.

The upper handles are able to rotate on their mounting relative to the trunk. The handles can occupy a first position in which the bars that extend from the cross-bar to the hand grip are generally parallel to the longitudinal extent of the trunk. This allows the hand grips to be engaged to allow an upper operator to pull the chair upstairs or to lower the chair downstairs. To ensure that the upper operator can maintain an advantageous lifting or weight bearing position the cross bar is mounted on a rod that is telescopically located within the trunk. A retractable spigot (not shown) extends through the trunk and can be selectively engaged in one of a series of, for instance, eight openings in the rod to locate the rod in the required telescopic position relative to the trunk.

With the rod being extended from the trunk, the chair is adapted for easy lowering down particularly steep stairs with a favourable operator position.

With the rod being collapsed within the trunk the configuration is compact for storage. In that position the bars that extend away from the cross bar may extend downwardly or parallel to the spine to occupy a compact storage configuration.

The bars that extend from the cross bar may also extend rearwardly of the trunk, or rearwardly and downwardly relative to the trunk. This is a particularly favourable position for an operator to be able to engage the hand grips and tilt the chair back slightly for manoeuvring on flat ground or to allow the c-.ai' to apcroa-h stairs.

The upper and lower handles are each mounted on a cross-bar that extends through a socket. A retractable spigot may extend through the socket to allow one of a selected series of holes in the cross-bars to be engaged to hold the cross- bar and thus the handles in the required angular position.

In applications where any of the chairs referred to herein have to be used on soft ground such as sand at the beach for example, the wheel sets previously described may tend to sink into the ground which may render movement of the chair difficult. Consequently an additional set of wheels 200 shown in Figure 10 are provided with the set being attachable to either and preferably both sides of the chair. The set 200 are not "handed" and are able to be secured to the right or left hand side of the sets of existing wheels.

The additional set of wheels each include three wheels 202 which are each rotatable about their own axis by being pivotally mounted on a common pair of brackets 204 as previously described in relation to the other sets.

Each additional set 204 has a disc 206 that is secured to a shaft 208 that extends between the brackets and about which the brackets may rotate. Projecting outwardly from the spacer disc 206 is a continuation of the shaft 208 which includes stub shafts 210 extending partially through the shaft and which are fixed thereto and which project radially from the shaft 208 for a small distance. The axial end of the shaft includes an axially extending threaded portion in which a stub housing 212 is screwed.

A ball 214 has a minor part of its volume extending from the end of the stub housing with a reduced diameter portion of the stub housing 212 preventing the ball from leaving. The ball 214 is biased into the position shown by a compression spring 216 contained in the housing.

The existing wheel sets each have a cup attachment 218 secured to the outer bracket as shown in Figures 1, 13 and 14. The cup attachment comprises a cylindrical housing 220 having one axial face 222 that is secured to the bracket and with an inwardly directed flange 224 having a circular opening 226 at the other axial end.

Diametrically opposed slots 228 extend outwardly from the circular opening 226.

In order to attach an additional set of wheels to the existing set, the projecting stub shafts of the additional set are aligned with the slots 228 in the existing set.

The additional set ls then urged towards the existing set to cause the stub shafts 210 to move past the flanges 224 against the bias of the spring 216 occasioned by the ball 214 abutting the bracket of the permanent set of wheels (or the axle of the permanent set) and being pushed into the housing 22. The additional set is then rotated slightly such that the stub shafts 210 move away from the slots 228. The additional set is then held in place with the stub shafts being biased against the flange 224 under the partial insertion of the ball 214 into the stub housing against the action of the spring.

The above attachment operation may be effected whilst the chair is on its side or lifted slightly. When the chair is back on the ground the additional set will abut the ground to enable alignment of the axes of the wheels of to'- additional set with the axes of the wheels of the existing set as a result of a small rotation of the stub shafts relative to the cup attachment 218.

The additional set of wheels are spaced slightly from the existing set.

The chair now has two sets of wheels at each side which greatly reduces the pressure on each wheel in contact with a surface and allows the chair to be moved over a soft surface without sinking in to such an extent. The chair can be manoeuvred over flat ground and up and down steps as previously described. The additional set, whilst not being directly braked or locked will nevertheless follow the existing set of wheels.

Removal of the additional set is a reversal of the attachment sequence.

Figures 1, 2 and 3 show, at 230, where a break in the trunk or spine 38 is made. The trunk is separable at this point to provide a lower half having the wheel sets and foot rest attached to it and an upper half with the handle, seat and backrest attached. With the upper half in the folded position shown in Figure 2, the trunk of the lower half can be attached to the trunk of the upper half, for instance by pushing the trunk of the lower half into two spaced clips 232. The clips 232 are themselves clipped onto the upper part of the trunk. The wheels of the lower half could face inwardly or outwardly with respect to the upper half and may be located facing the handle or facing away from the handle.

Figures 15, 16 and 17 show details of how the trunk is divided into an upper portion 38A and a lower portion 38B.

The upper portion 38A includes an inverted cup 234 that extends over the open end of the hollow trunk and into the trunk. The cup 234 is held in place by bolts 236 that hold the foot rest in place on its pivotal mounting with the bolts extending, from opposite sides, through the trunk and cup and into the cup.

The lower portion 38B includes a connector 238 that extends into and out of the open end of the lower part of the trunk 38B. The connector is held on the trunk by rivets 240 (only one of which is shown). A radial rim 242 sits on the upper edge of the trunk and a cylindrical projection 244 extends from the trunk with that projection having a slot 246 through it.

To assemble the two parts of the trunk, the upper part 38A is slid down onto the lower half so that the cylindrical projection lies closely within the cup until the rim 242 abuts against a corresponding rim 248 on the cup.

Relative angular movement is prevented by the bolts 236 extending into the slot 246.

In an alternative configuration (not shown) the upper and lower parts are pivotally connected to each other about the junction between the rearwardly facing portion of the parts 38A and 38B. A catch may be provided at the forwardly facing junction of the upper and lower parts to hold them in the operative position. When the catch is released the parts can be moved to the storage position by pivoting the lower part relative to the upper part. In the storage position the clips 232 may again hold the two parts together.

A bolt (not shown) passes through aligned holes 250 in the upper part of the trunk and cup and in the cylindrical projection with the bolt extending to either side of the trunk. The bolt may include projections at one end which prevent retraction of the bolt but which can be released by depressing a plunger at the other end.

The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

S All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features

disclosed in this specification (including any

accompanying claims abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. Patient transport means including a support means for a patient and wheels including at least one set of wheels with the or each set comprising at least two wheels each rotatable about their own axis and each rotatable about a common axis attached to the transportation means which enable the transportation means to travel, characterized in that at least one further set of wheels is provided with the or each further set comprising at least two wheels each rotatable about their own axis and each rotatable about a common axis which may be selectively attached and detached from the transportation means and thereby the transportation means is able to be more manoeuvrable on a softer surface.

2. Patient transport means as claimed in claim 1 in which the further set of wheels is arranged to be attached to an existing set of wheels.

3. Patient transport means as claimed in claim 2 in which the further set of wheels is arranged to be attached to an existing set of wheels such that the rotational axes of wheels in each set are aligned.

4. Patient transport means as claimed in any preceding claim in which the further wheels have the same inflation pressure as the wheels that were present on the transportation means before the attachment of the further wheels.

5. Patient transport means as claimed in any preceding claim in which the further wheels have the same resistance to pressure as the wheels that were present on the transportation means before the attachment of the further wheels.

6. Patient transport means as claimed in any preceding claim in which the further wheels have the same friction properties as the wheels that were present on the transportation means before the attachment of the further wheels.

7. Patient transport means as claimed in any preceding claim in which the further wheels are detachably connected by axial and turning motion.

8. Patient transport means as claimed in claim 7 in which the further wheels are detachably connected by axial and turning motion with that movement locating a part on one of the further wheels or the wheel behind another part to prevent axial movement to detach the further wheels.

9. Patient transport means as claimed in claim 7 or 8 in which the axial movement is arranged to be against a resilient bias.

10. Patient transport means as claimed in claim 9 in which the resilient bias remains when the further wheels are connected.

11. Patient transport means as claimed in any preceding claim in which the sets of wheels are rotatable about a common axis.

12. Patient transport means as claimed in claim 11 in which the common axis is parallel to each wheel axis of the set and is spaced from each wheel axis of the set.

13. Patient transport means as claimed in claim it or 12 in which the common axis is equidistant from each wheel axis.

14. A method of adapting a patient transport chair as claimed in either of claims 12 or 13 when the transportation means are as claimed in any of claims 1 to 11.

14. Patient transport means including a support means for a patient and wheels attached to the transportation means substantially as herein described with reference to, and as shown in any of Figures 10 to 14 when taken in conjunction with any Of Figures 1 to 9 and 15 to 17.

15. A method of adapting patient transportation means including at least one set of wheels with the or each set comprising at least two wheels each rotatable about their own axis and each rotatable about a common axis attached to the transportation means comprising connecting at least one further set of wheels comprising at least two wheels each rotatable about their own axis and each rotatable about a common axis to the transportation means whereby the transportation means is able to be more manoeuvrable on a softer surface.

16. A method as claimed in claim 15 comprising adding the further set to the existing set.

17. A method of adapting patient transportation means substantially as herein described and with reference to, and as shown in any of Figures 10 to 14 when taken in conjunction with any of Figures 1 to 9 and 15 to 17.

18. A method of adapting patient transportation means as claimed lo any of claims i5 to 17 when the transportation means are as claimed in any of claims 1 to 14.

Amendments to the claims have been filed as follows no

1. A patient transport chair including a support means for a patient and wheels including at least one set of wheels with the or each set comprising at least two wheels each rotatable about their own axis and each rotatable about a common axis attached to the transportation means which enable the transportation means to travel, characterized in that at least one further set of wheels lo is provided with the or each further set colpliilly at least two wheels each rotatable about their own axis and each rotatable about a common axis with the common axis of the further set of wheels and the axes of the wheels of the further set of wheels that are each rotatable about their own axes each being aligned with a corresponding axle AL the at least one set of wheels whicl^l fu'- tl^e' so.

may be selectively attached and detached from the transportation means and thereby the transportation means is able to be more manoeuvrable on a softer surface.

2. A chair claimed in claim 1 in which the further set of wheels is arranged to be attached to an existing set of wheels.

3. A chair as claimed in any preceding claim in which the further wheels have the same inflation pressure as the wheels that were present on the transportation means before the attachment of the further wheels.

4. A chair as claimed in any preceding claim in which the further wheels have the same resistance to pressure as clan wheels LI^at were piesent on the tla..spo'^taton means before the attachment of the further wheels. 4/

5. A chair as claimed in any preceding claim in which the further wheels have the same friction properties as the wheels that were present on the transportation means before the attachment of the further wheels.

6. A chair as claimed in any preceding claim in which the further wheels are detachably connected by axial and turning motion.

7. A chair as claimed in claim 6 in which the further set of wheels are detachably connected by axial and turning motion with that movement locating a part on one wheel of the further set of wheels behind another part to on the at least one set to prevent axial movement to detach the further wheels.

8. A chair as claimed in claim 6 or 7 in which the axial movement is arranged to be against a resilient bias.

9. A chair as claimed in claim 8 in which the resilient bias remains when the further wheels are connected.

10. A chair as claimed in any preceding claim in which the common axis is parallel to each wheel axis of the set and is spaced from each wheel axis of the set.

11. A chair as claimed In any preceding claim in which the common axis is equidistant from each wheel axis.

12. A method of adapting a patient transportation chair including at least one set of wheels with the or each Sat comprising at least two wheels each rotatable about their own axis and each rotatable about a common axis attached to the transportation means comprising connecting at least one further set of wheels comprising at least two wheels each rotatable about their own axis and each rotatable about a common axis to the transportation means with the common axis of the further set of wheels and the axes of the wheels of the further set of wheels that are each rotatable about their own axes each being aligned with a corresponding axis of the at least one set of wheels whereby the transportation means is able to be more manoeuvrable on a softer surface.

13. A method as claimed in claim 12 comprising adding the further set to the existing set.